DS1689SN+ Real Time Clock IC Equivalent & Substitute Parts

Part Overview

The DS1689SN+ is a Real Time Clock (RTC) IC with integrated Clock/Calendar functionality and NVSRAM, manufactured by Analog Devices Inc./Maxim Integrated. This component operates across dual voltage ranges (2.7V–3.3V and 4.5V–5.5V) with battery backup capability, housed in a 28-SOIC surface mount package. The product is currently obsolete, necessitating identification of functionally equivalent alternatives for ongoing system support and new designs requiring RTC Clock/Calendar functionality with parallel interface architecture.

Substiute Parts

DS1689SN+

Analog Devices Inc./Maxim IntegratedIn Stock: 2115DS1689SN+ Datasheet

Current PartRFQ

BQ4802YDW

BenchmarqIn Stock: 1824BQ4802YDW Datasheet

MFR RecommendedRFQ

M48T02-150PC1

STMicroelectronicsIn Stock: 1525M48T02-150PC1 Datasheet

MFR RecommendedRFQ

M48T35AV-10MH1F

STMicroelectronicsIn Stock: 5879M48T35AV-10MH1F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the DS1689SN+ is determined by the following critical parameters:

Primary Compatibility Criteria:

• Interface type: Parallel (mandatory match)
• Time format: HH:MM:SS with 12/24 hour capability
• Date format: YY-MM-DD-dd
• Package type: 28-pin surface mount configuration
• Voltage supply ranges: Compatibility with 2.7V–3.3V and/or 4.5V–5.5V operation
• Battery backup voltage: 2.5V–3.7V range

Substitution Logic: Substitute parts must maintain parallel interface architecture and support equivalent time/date formats. Package form factor and mounting type determine physical PCB compatibility. Voltage supply specifications define circuit integration feasibility. Parts with overlapping voltage ranges and matching functional specifications are classified as direct substitutes.

Parameter Comparison

Engineering Selection Recommendations

BQ4802YDW (Benchmarq): Active product status with parallel interface and matching time/date formats. Operates within 4.5V–5.5V supply range, compatible with the DS1689SN+ 5V operation mode. 28-SOIC surface mount package maintains PCB footprint compatibility. Battery backup range (2.4V–4V) overlaps with DS1689SN+ specification. Operating temperature range (0°C–70°C) is narrower than the original part. ROHS3 compliance status not specified in provided data.

M48T02-150PC1 (STMicroelectronics): Active product with Timekeeper® series designation. Parallel interface with matching date format. Through-hole 24-DIP package requires PCB redesign compared to surface mount DS1689SN+. Operates within 4.75V–5.5V supply range, compatible with 5V operation. 24-hour time format differs from DS1689SN+ 12/24-hour capability. ROHS3 compliant. Battery backup voltage not specified.

M48T35AV-10MH1F (STMicroelectronics): Active product with Timekeeper® series designation. Parallel interface with matching date format. 28-SOP surface mount package with SNAPHAT Sockets provides form factor compatibility. Operates within 3V–3.6V supply range, compatible with DS1689SN+ 3.3V operation mode. 24-hour time format differs from DS1689SN+ 12/24-hour capability. ROHS3 compliant. Moisture Sensitivity Level 3 (168 Hours) versus DS1689SN+ MSL 1.

Frequently Asked Questions (FAQ)

Q: Can BQ4802YDW directly replace DS1689SN+ in existing designs? A: BQ4802YDW maintains parallel interface, matching time/date formats, and 28-SOIC surface mount package. Voltage supply compatibility exists for 5V operation. Operating temperature range is narrower (0°C–70°C versus -40°C–85°C). Functional substitution is feasible for applications within the BQ4802YDW temperature specification.

Q: What are the package compatibility implications of M48T02-150PC1? A: M48T02-150PC1 uses through-hole 24-DIP packaging versus DS1689SN+ surface mount 28-SOIC. PCB layout redesign is required. Pin count differs (24 versus 28), necessitating schematic and board-level modifications.

Q: How do voltage supply ranges affect substitution decisions? A: DS1689SN+ supports dual voltage ranges (2.7V–3.3V and 4.5V–5.5V). BQ4802YDW operates only at 4.5V–5.5V. M48T35AV-10MH1F operates only at 3V–3.6V. Selection depends on target system voltage. Designs requiring both voltage ranges cannot use single-range substitutes without additional power management circuitry.

Q: What is the significance of time format differences? A: DS1689SN+ supports both 12-hour and 24-hour formats. M48T02-150PC1 and M48T35AV-10MH1F support 24-hour format only. Firmware or application-level adjustments may be required if 12-hour format operation is mandatory.

Q: Are there temperature range limitations with substitute parts? A: All substitute parts operate within 0°C–70°C range, narrower than DS1689SN+ (-40°C–85°C). Applications requiring extended temperature operation below 0°C or above 70°C cannot use these substitutes.

Q: What moisture sensitivity considerations apply? A: DS1689SN+ has MSL 1 (Unlimited). M48T35AV-10MH1F has MSL 3 (168 Hours), requiring stricter moisture control during storage and assembly. M48T02-150PC1 has MSL 1. Handling procedures must align with component MSL classification.